Field of the Invention
The present invention relates to an electrode material for batteries, an electrode material paste for batteries, a method for manufacturing the electrode material for batteries, a dye-sensitized solar cell, and a storage battery.
Description of Related Art
In recent years, solar cells for which solar energy available as natural energy can be utilized have been a focus of attention.
Initially, a silicon-based solar cell has been used mainly as the solar cell. The silicon-based solar cell has the advantage of being able to achieve a power generation efficiency of no less than 10%.
Vacuum film-forming techniques, such as the crystal growth of silicon and sputtering, are frequently used, however, in order to manufacture the silicon-based solar cell. Accordingly, the silicon-based solar cell is high in manufacturing cost.
Hence, as a technology in which the manufacturing cost of solar cells is decreased, studies are being made of a dye-sensitized solar cell formed by fixating a light-absorbing dye on the surfaces of fine particles of a semiconductor other than silicon. This dye-sensitized solar cell is fabricated by fixating a dye on the surfaces of semiconductor fine particles. Accordingly, paste coating techniques are frequently used in the fabrication of the dye-sensitized solar cell.
For example, Patent Document 1 (Japanese Patent Laid-Open No. 2008-204956) describes that a specific degree of power generation efficiency can be attained by using titanium oxide powder as an electrode material and fixating a dye on the particle surfaces of this titanium oxide powder. According to the technique described in Patent Document 1, it is possible to reduce manufacturing costs.
Since a solar cell literally uses solar light, the amount of electrical generation varies depending on the amount of solar insolation. Accordingly, the solar cell has been problematic in that if the amount of solar insolation drastically decreases, as in the case of, for example, the solar cell being moved from an outdoor location into an indoor location during daytime hours, the amount of electrical generation drastically decreases as well.    As a technology to cope with such a change in the amount of solar insolation, Patent Document 2 (Japanese Patent Laid-Open No. 2009-135025) describes a technique of providing a dye-sensitized solar cell with an electricity storage function by disposing a solid electricity storage layer on a photoelectric conversion layer.